The Copenhagen Diagnosis - Interim Climate Science Report

A team of climate scientists has produced The Copenhagen Diagnosis, a summary of peer-reviewed science on the anticipated impacts of anthropogenic climate change.

The purpose of this report is to synthesize the most policy-relevant climate science published since the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). Since then, many hundreds of papers have been published on a suite of topics related to human-induced climate changes. The report serves as an interim evaluation of the evolving science, and as a handbook of science updates that supplements the IPCC AR4. (IPCC AR5 is not due for completion until 2013.)

Despite recent revelations and controversy over some data sets and scientists’ actions, the report authors believe that world leaders still have plenty of topics to discuss during the UN Climate Change meeting that begins next week in Copenhagen.

New Benchmark for CO2?

In an interview with Agence France Presse, Rajendra Pachauri, the UN's top climate scientist and head of the Intergovernmental Panel on Climate Change, stated the following when asked if he supported calls to keep atmospheric carbon dioxide concentrations below 350 parts per million (ppm):

"As chairman of the Intergovernmental Panel on Climate Change (IPCC) I cannot take a position because we do not make recommendations, but as a human being I am fully supportive of that goal. What is happening, and what is likely to happen, convinces me that the world must be really ambitious and very determined at moving toward a 350 target."

The IPCC's last report, which came out in the winter of 2007, didn't actually set a target for CO2, but it was widely interpreted as backing a goal of 450 ppm, a number that many environmental groups and governments (including the Obama administration) have since embraced.

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